Amino functionalized PEGylated silica nanoparticles were prepared by one pot-procedure, based on ammonia catalysed hydrolysis and polycondensation of Tetraethoxysilane (TEOS) and 3-Aminopropyltriethoxysylane (APTS), in alcohol medium (ethanol) (Sather method), containing PEG 5000 monomethyl ether. Particles size was studied using Transmission Electron Spectroscopy (TEM). PEGylation and amino functionalization was investigated through FT-IR and Thermogravimetric analysis (TG). The structure of nanoparticles consists of nanosilica (a few nanometers in size) dispersed into a PEG matrix, produced by entanglement of PEG chains. The stability of the water colloidal suspension depends on the PEG/silica mass ratio, that changes with PEG concentration in the reaction batch. By properly selecting the PEG concentration, nanoparticles smaller than 150 nm were obtained, stable towards aggregation in water media up to 6 months. The observed need of an optimal PEG/silica mass ratio for long-term stability can be explained on the basis of particles structure and assuming that both steric and electrostatic effect concur to stabilisation. (C) 2010 Elsevier BM. All rights reserved.
Synthesis structure and stability of amino functionalized PEGylated silica nanoparticles / Branda, Francesco; Silvestri, Brigida; Luciani, Giuseppina; Costantini, Aniello; F., Tescione. - In: COLLOIDS AND SURFACES. A, PHYSICOCHEMICAL AND ENGINEERING ASPECTS. - ISSN 0927-7757. - ELETTRONICO. - 367:(2010), pp. 12-16. [10.1016/j.colsurfa.2010.05.036]
Synthesis structure and stability of amino functionalized PEGylated silica nanoparticles
BRANDA, FRANCESCO;SILVESTRI, BRIGIDA;LUCIANI, GIUSEPPINA;COSTANTINI, ANIELLO;
2010
Abstract
Amino functionalized PEGylated silica nanoparticles were prepared by one pot-procedure, based on ammonia catalysed hydrolysis and polycondensation of Tetraethoxysilane (TEOS) and 3-Aminopropyltriethoxysylane (APTS), in alcohol medium (ethanol) (Sather method), containing PEG 5000 monomethyl ether. Particles size was studied using Transmission Electron Spectroscopy (TEM). PEGylation and amino functionalization was investigated through FT-IR and Thermogravimetric analysis (TG). The structure of nanoparticles consists of nanosilica (a few nanometers in size) dispersed into a PEG matrix, produced by entanglement of PEG chains. The stability of the water colloidal suspension depends on the PEG/silica mass ratio, that changes with PEG concentration in the reaction batch. By properly selecting the PEG concentration, nanoparticles smaller than 150 nm were obtained, stable towards aggregation in water media up to 6 months. The observed need of an optimal PEG/silica mass ratio for long-term stability can be explained on the basis of particles structure and assuming that both steric and electrostatic effect concur to stabilisation. (C) 2010 Elsevier BM. All rights reserved.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.
